School bond measures proposed for Carlsbad and Vista schools would pay for new science labs and classrooms, improved security and modern technology in those districts, while a Bonsall bond measure would pay to build a new high school and improve existing campuses.

If approved, the three North County school bond measures would generate more than a half-billion dollars for school construction and upgrades at local campuses.

The Carlsbad bond issue, Measure HH, would authorize Carlsbad Unified School District to issue $265 million in school bonds over a 30-year period, at an annual cost of $34 per $100,000 of assessed property value. An analysis of the measure by the San Diego Taxpayers Association concluded that its total cost, with interest and principal, would be $508 million. The money would go to upgrade classrooms and science labs, renovate deteriorating roofs, plumbing and other infrastructure, modernize computer systems and improve campus security.

Vista’s proposal, Measure LL, calls for $247 million in general obligation bonds, at a cost of $30 per $100,000 in assessed value per year. According to the taxpayers association, it will cost $506 million, including interest and principal, over the life of the bond. The majority of that would pay to replace the portable structures that make up more than half of the district’s classrooms, and the rest would cover upgrades to security and technology systems, Superintendent Linda Kimble said.

Bonsall’s bond issue, Measure EE, would raise $38 million, at $37.50 per $100,000 of assessed property value each year to build a high school, and to renovate track and field facilities and install security systems at existing campuses. The taxpayers association estimates its total cost will be $78 million.

In Carlsbad, the district aims to update its schools, several of which were built in the 1950s. The new bond issue follows Proposition P, the 2007 bond measure which paid to build Sage Creek High School and modernize Carlsbad High School. It turned its attention next to tackling the backlog of maintenance, school safety and upgrades needed at its other campuses.

“Districtwide, we are first improving safety and security,” Superintendent Ben Churchill said at a recent “State of the District” event. “This is absolutely front of mind for all of us these days. We’re also looking at sustainability and energy efficiency.”

After working with local law enforcement, firefighters and the U.S. Department of Homeland Security, the district has drawn up plans to harden its campuses against intruders. The bond measure would cover parts of that plan that require investments in equipment, such as fencing, controlled entrances, security cameras and digital scanning of drivers’ licenses to provide real-time background checks.

In addition, the district aims to install solar panels and battery storage to offset the $2 million it spends on energy each year, Churchill said.

Other priorities stem from the district’s facilities master plan, which lays out a blueprint for preparing students for high-wage jobs in high demand, including health care, biomedical science, computer science, robotics and skilled trades.

According to the master plan, libraries would be renovated as research centers, with flexible space and digital resources, in addition to books. Elementary schools could get “maker spaces” with gear such as 3D printers and sound equipment.

“We’re working to make sure that our educational environments look just like the world of work,” Churchill said.

In Vista, the school bond issue would largely pay to replace aging portable classrooms. Of the $247 million the bond would raise, $187 million would go to replace relocatable classroom buildings with modern, permanent facilities, Superintendent Linda Kimble said.

At Vista schools, 457 classrooms -- or 56 percent of total classrooms — are housed in relocatable buildings, according to the district. More than half of those are more than 25 years old, and don’t support the innovative education that Vista strives for, school officials said.

“For a property owner in Vista, you want schools you can be proud of that prepare the (students) in Vista for future college and career,” Kimble said. “You want schools that look great and have a great reputation, because that not only helps the kids, but it also improves your property value.”

That makes it troublesome and pricey to maintain the buildings, said Scott Conley, lead custodian at Roosevelt Middle School. There, many students attend classes in 30-year-old portables that were placed on site when the school was built. They were meant to be temporary quarters during the construction, but they were never removed, and remain in use today, said Principal Heather Golly.

Conley and his crew stay busy reinforcing areas of the buildings that are crumbling from dry rot. When it rains, they’re called in to handle leaky roofs in classrooms, and they keep a close watch on rodents that can burrow into the structures through holes in the walls.

Although voters passed a $140 million bond issue, Proposition O, in 2002, to build new schools and repair older ones, there is still more work to do, school officials said.

If the bond passes, the district would construct new, two-story classroom buildings and install energy-efficient heating and cooling. It would reinforce security with intrusion alarms, video surveillance cameras, safety locks, fencing, gates and lighting.

And it would "create 21st Century learning environments,” with updated computer networks, sound systems and visual technology; new science labs, art and music facilities, and classroom space for career education at several campuses.

“I think I have amazing students and they deserve the best structures: safe, updated and preparing them for the future,” Golly said.

Plans for a new, state-of-the-art high school on Gird Road, off State Route 76, have been on the table for years, as residents in the rural neighborhood have fought the project, claiming the site poses safety, traffic and environmental problems. They have fended off multiple bond measures for the campus, most recently campaigning to defeat a $58 million bond issue in 2016.

For now, the district’s high school students share a campus with Sullivan Middle School on West Lilac Road, but officials say the school will need its own campus to accommodate increased enrollment as Bonsall grows following the recent widening of State Route 76.

In addition to construction of the high school, the bond issue would provide several million dollars for security projects including camera surveillance, electronic security systems, fencing and access improvements, as well as upgrades to track and field facilities.

This story was updated to reflect the correct title of Bonsall’s school bond, Measure EE.